Multi-Source Documentation MCP Server

--- category: reference source: claude-code title: CLI Reference url: https://code.claude.com/docs/en/cli-reference --- ##### Reference - [CLI reference](/docs/en/cli-reference) - [Interactive mode](/docs/en/interactive-mode) - [Slash commands](/docs/en/slash-commands) - [Checkpointing](/docs/en/checkpointing) - [Hooks reference](/docs/en/hooks) - [Plugins reference](/docs/en/plugins-reference) On this page - [CLI commands](#cli-commands) - [CLI flags](#cli-flags) - [Agents flag format](#agents-flag-format) - [System prompt flags](#system-prompt-flags) - [See also](#see-also) ## [​](#cli-commands) CLI commands | Command | Description | Example | | --- | --- | --- | | `claude` | Start interactive REPL | `claude` | | `claude "query"` | Start REPL with initial prompt | `claude "explain this project"` | | `claude -p "query"` | Query via SDK, then exit | `claude -p "explain this function"` | | `cat file | claude -p "query"` | Process piped content | `cat logs.txt | claude -p "explain"` | | `claude -c` | Continue most recent conversation | `claude -c` | | `claude -c -p "query"` | Continue via SDK | `claude -c -p "Check for type errors"` | | `claude -r "<session-id>" "query"` | Resume session by ID | `claude -r "abc123" "Finish this PR"` | | `claude update` | Update to latest version | `claude update` | | `claude mcp` | Configure Model Context Protocol (MCP) servers | See the [Claude Code MCP documentation](/docs/en/mcp). | ## [​](#cli-flags) CLI flags Customize Claude Code’s behavior with these command-line flags: | Flag | Description | Example | | --- | --- | --- | | `--add-dir` | Add additional working directories for Claude to access (validates each path exists as a directory) | `claude --add-dir ../apps ../lib` | | `--agents` | Define custom [subagents](/docs/en/sub-agents) dynamically via JSON (see below for format) | `claude --agents '{"reviewer":{"description":"Reviews code","prompt":"You are a code reviewer"}}'` | | `--allowedTools` | A list of tools that should be allowed without prompting the user for permission, in addition to [settings.json files](/docs/en/settings) | `"Bash(git log:*)" "Bash(git diff:*)" "Read"` | | `--disallowedTools` | A list of tools that should be disallowed without prompting the user for permission, in addition to [settings.json files](/docs/en/settings) | `"Bash(git log:*)" "Bash(git diff:*)" "Edit"` | | `--print`, `-p` | Print response without interactive mode (see [SDK documentation](https://docs.claude.com/en/docs/agent-sdk) for programmatic usage details) | `claude -p "query"` | | `--system-prompt` | Replace the entire system prompt with custom text (works in both interactive and print modes; added in v2.0.14) | `claude --system-prompt "You are a Python expert"` | | `--system-prompt-file` | Load system prompt from a file, replacing the default prompt (print mode only; added in v1.0.54) | `claude -p --system-prompt-file ./custom-prompt.txt "query"` | | `--append-system-prompt` | Append custom text to the end of the default system prompt (works in both interactive and print modes; added in v1.0.55) | `claude --append-system-prompt "Always use TypeScript"` | | `--output-format` | Specify output format for print mode (options: `text`, `json`, `stream-json`) | `claude -p "query" --output-format json` | | `--input-format` | Specify input format for print mode (options: `text`, `stream-json`) | `claude -p --output-format json --input-format stream-json` | | `--include-partial-messages` | Include partial streaming events in output (requires `--print` and `--output-format=stream-json`) | `claude -p --output-format stream-json --include-partial-messages "query"` | | `--verbose` | Enable verbose logging, shows full turn-by-turn output (helpful for debugging in both print and interactive modes) | `claude --verbose` | | `--max-turns` | Limit the number of agentic turns in non-interactive mode | `claude -p --max-turns 3 "query"` | | `--model` | Sets the model for the current session with an alias for the latest model (`sonnet` or `opus`) or a model’s full name | `claude --model claude-sonnet-4-5-20250929` | | `--permission-mode` | Begin in a specified [permission mode](/docs/en/iam#permission-modes) | `claude --permission-mode plan` | | `--permission-prompt-tool` | Specify an MCP tool to handle permission prompts in non-interactive mode | `claude -p --permission-prompt-tool mcp_auth_tool "query"` | | `--resume` | Resume a specific session by ID, or by choosing in interactive mode | `claude --resume abc123 "query"` | | `--continue` | Load the most recent conversation in the current directory | `claude --continue` | | `--dangerously-skip-permissions` | Skip permission prompts (use with caution) | `claude --dangerously-skip-permissions` | The `--output-format json` flag is particularly useful for scripting and automation, allowing you to parse Claude’s responses programmatically. ### [​](#agents-flag-format) Agents flag format The `--agents` flag accepts a JSON object that defines one or more custom subagents. Each subagent requires a unique name (as the key) and a definition object with the following fields: | Field | Required | Description | | --- | --- | --- | | `description` | Yes | Natural language description of when the subagent should be invoked | | `prompt` | Yes | The system prompt that guides the subagent’s behavior | | `tools` | No | Array of specific tools the subagent can use (e.g., `["Read", "Edit", "Bash"]`). If omitted, inherits all tools | | `model` | No | Model alias to use: `sonnet`, `opus`, or `haiku`. If omitted, uses the default subagent model | Example: Copy Ask AI ```shiki claude --agents '{ "code-reviewer": { "description": "Expert code reviewer. Use proactively after code changes.", "prompt": "You are a senior code reviewer. Focus on code quality, security, and best practices.", "tools": ["Read", "Grep", "Glob", "Bash"], "model": "sonnet" }, "debugger": { "description": "Debugging specialist for errors and test failures.", "prompt": "You are an expert debugger. Analyze errors, identify root causes, and provide fixes." } }' ``` For more details on creating and using subagents, see the [subagents documentation](/docs/en/sub-agents). ### [​](#system-prompt-flags) System prompt flags Claude Code provides three flags for customizing the system prompt, each serving a different purpose: | Flag | Behavior | Modes | Use Case | | --- | --- | --- | --- | | `--system-prompt` | **Replaces** entire default prompt | Interactive + Print | Complete control over Claude’s behavior and instructions | | `--system-prompt-file` | **Replaces** with file contents | Print only | Load prompts from files for reproducibility and version control | | `--append-system-prompt` | **Appends** to default prompt | Interactive + Print | Add specific instructions while keeping default Claude Code behavior | **When to use each:** - **`--system-prompt`**: Use when you need complete control over Claude’s system prompt. This removes all default Claude Code instructions, giving you a blank slate. Copy Ask AI ```shiki claude --system-prompt "You are a Python expert who only writes type-annotated code" ``` - **`--system-prompt-file`**: Use when you want to load a custom prompt from a file, useful for team consistency or version-controlled prompt templates. Copy Ask AI ```shiki claude -p --system-prompt-file ./prompts/code-review.txt "Review this PR" ``` - **`--append-system-prompt`**: Use when you want to add specific instructions while keeping Claude Code’s default capabilities intact. This is the safest option for most use cases. Copy Ask AI ```shiki claude --append-system-prompt "Always use TypeScript and include JSDoc comments" ``` `--system-prompt` and `--system-prompt-file` are mutually exclusive. You cannot use both flags simultaneously. For most use cases, `--append-system-prompt` is recommended as it preserves Claude Code’s built-in capabilities while adding your custom requirements. Use `--system-prompt` or `--system-prompt-file` only when you need complete control over the system prompt. For detailed information about print mode (`-p`) including output formats, streaming, verbose logging, and programmatic usage, see the [SDK documentation](https://docs.claude.com/en/docs/agent-sdk). ## [​](#see-also) See also - [Interactive mode](/docs/en/interactive-mode) - Shortcuts, input modes, and interactive features - [Slash commands](/docs/en/slash-commands) - Interactive session commands - [Quickstart guide](/docs/en/quickstart) - Getting started with Claude Code - [Common workflows](/docs/en/common-workflows) - Advanced workflows and patterns - [Settings](/docs/en/settings) - Configuration options - [SDK documentation](https://docs.claude.com/en/docs/agent-sdk) - Programmatic usage and integrations [Interactive mode](/docs/en/interactive-mode) ⌘I